US4282738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for adjusting stroke length of a ram for presses
Assignee: Amada Co Ltd
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Filing: 1979-04-02
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Granted: 1981-08-11
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Expires: 1999-04-02
Abstract
Abstract This invention relates to a method and apparatus for adjusting a stroke length of a ram for a press. The stroke length of the ram is adjusted with respect to a base point. The hydraulic pressure level in the acting chanber is also adjusted. The press is generally used for bending metal sheets. By this invention, an optimum stroke length of the ram in the press can be easily determined without experimentally processing and, therefore, wasting sheet metal workpieces.
Inventors
- 👤 Shigenori Kojima
- 👤 Katsumi Koyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:03
CPC Classifications
B; B21; B21D; B21D5/00; B21D5/02; B30; B30B; B30B15/00; B30B15/16; B30B15/18
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
205 words
An apparatus for adjusting a stroke length of a ram for a press, comprising: a ram; a first tool held by the ram; a frame aligned in opposition to the ram; a second tool held by the frame; hydraulic driving means for raising and lowering the ram; rotary encoder means for detecting a point where said first and second tools are completely engaged with each other at a predetermined hydraulic pressure in the driving means; control means for setting said point as a base point from which a stroke length of the ram is thereafter measurable with respect to said second tool, for storing said point as the base point, and for transmitting signals; whereby the stroke length of the ram is adjusted with respect to said base point; stopper means for stopping the ram at a desired position, said stopper means being adjustably provided on the frame; a hydraulically acting chamber, provided in the driving means, for raising the ram; check valve means for communicating with the acting chamber; and a push rod means for contacting the stopper means at one end and for pushing the check valve means at its other end; whereby the hydraulic pressure level in the acting chamber is adjusted.
Claim 2
Independent Claim
205 words
An apparatus for adjusting a stroke length of a ram for a press, comprising: a ram; a first tool held by the ram; a frame aligned in opposition to the ram; a second tool held by the frame; hydraulic driving means for raising and lowering the ram; rotary encoder means for detecting a point where said first and second tools are completely engaged with each other at a predetermined hydraulic pressure in the driving means; control means for setting said point as a base point from which a stroke length of the ram is thereafter measurable with respect to said second tool, for storing said point as the base point, and for transmitting signals; whereby the stroke length of the ram is adjusted with respect to said base point; stopper means for stopping the ram at a desired position, said stopper means being adjustably provided on the frame; a hydraulically acting chamber, provided in the driving means, for raising the ram; check valve means for communicating with the acting chamber; and a push rod means for contacting the stopper means at one end and for pushing the check valve means at its other end; whereby the hydraulic pressure level in the acting chamber is adjusted.
Claim 3
Dependent Claim
40 words
The apparatus, according to claim 1, further comprising: means, provided on the frame, for holding the stopper means; and motor means for moving the stopper means along the holding means in response to the signals transmitted from the control means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-10 | 1985-02-09 | 1985-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-10 | 1989-02-09 | 1989-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-10 | 1993-02-09 | 1993-08-11 | $7700.00 | Window Closed / Lapsed |